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From:   Sergio Paracuellos <sergio.paracuellos@gmail.com>
Date:   Mon, 10 Jan 2022 11:59:22 +0100
Message-ID: <CAMhs-H_cCFsMs5VTrrNROBpfnwsXNLGGCFHSu2sJ8N-cxYV8aA@mail.gmail.com>
Subject: Re: [PATCH v6 3/4] clk: ralink: make system controller node a reset provider
To:     Philipp Zabel <p.zabel@pengutronix.de>
Cc:     "open list:COMMON CLK FRAMEWORK" <linux-clk@vger.kernel.org>,
        John Crispin <john@phrozen.org>, linux-staging@lists.linux.dev,
        Greg KH <gregkh@linuxfoundation.org>,
        NeilBrown <neil@brown.name>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        Stephen Boyd <sboyd@kernel.org>
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On Mon, Jan 10, 2022 at 11:23 AM Philipp Zabel <p.zabel@pengutronix.de> wrote:
>
> On Mon, 2022-01-10 at 10:39 +0100, Sergio Paracuellos wrote:
> [...]
> > > Is this known to work for all possible users, without delay between
> > > assert and deassert?
> >
> > It seems it is. This is based on the original reset implementation for
> > ralink. See:
> >
> > https://elixir.bootlin.com/linux/v5.16/source/arch/mips/ralink/reset.c#L55
> >
> > > Are there any users of the reset_control_reset() API at all? This API
> > > was added for self-clearing reset bits, so if there are no users that
> > > need to pretend this is a reset pulse at the hardware level (there may
> > > be), I'd prefer if this was just left out.
> >
> > I am not following you here. What do you mean?
>
> Looking at drivers/staging/mt7621-dts/mt7621.dtsi, it appears the
> current reset users are:
>   mediatek,mt7621-i2c
>   ralink,mt7621-spi
>   ralink,rt3883-gdma
>   mediatek,mt7621-hsdma
>   mediatek,mt7621-eth
>   mediatek,mt7621
>   mediatek,mt7621-pci
>
> Many of the corresponding drivers use device_reset(), which is a
> shorthand for requesting a reset control and calling
> reset_control_reset() on it. That will call mt7621_reset_device, so it
> is indeed used.
>

Ok, pretty clear now, thanks for clarification :).

> regards
> Philipp

Best regards,
    Sergio Paracuellos